Information Notice 1996-26, Recent Problems With Overhead Cranes
K>~UNITED STATESNUCLEAR REGULATORY COMMISSIONOFFICE OF NUCLEAR REACTOR REGULATIONWASHINGTON, D.C. 20555April 30, 1996NRC INFORMATION NOTICE 96-26: RECENT PROBLEMS WITH OVERHEAD CRANES
Addressees
All holders of operating licenses or construction permits for nuclear powerreactors.
Purpose
The U.S. Nuclear Regulatory Commission (NRC) is issuing this informationnotice to alert addressees to recent problems with overhead cranes. It isexpected that recipients will review the information for applicability totheir facilities and consider actions, as appropriate, to avoid similarproblems. However, suggestions contained in this information notice are notNRC requirements; therefore, no specific action or written response isrequired.
Description of Circumstances
Failure of Overhead Crane Bridge RailAt the Trojan Nuclear Plant on July 7, 1995, a section of the reactor buildingpolar crane bridge rail failed. The rail had a crack across the top of thetop flange and a piece of the flange had been displaced. The end of onesection of the rail had failed through the plane of the rail joint bar boltsextending up through the top flange. Visual and metallographic examination ofthe failure plane indicated that much of the failure was preexisting. Rust onthe failure surfaces and "peening" of some areas indicated that the initialcrack could extend back to the plant's construction.The licensee research of construction records determined that a nonconformancereport, dated July 26, 1972, noted that the rails were not slotted for boltsin accordance with the drawings. The corrective action recommended was to"burn the slots in the field." The licensee determined the cause of thefailure to be torsional shear and bending at the stress risers from the flame-cut holes. Flame cutting the slots left residual stresses in the materialbecause of the lack of careful preheating and controlled cooling. Also, sharpnotches, noted in the area of the flame cutting, concentrated the stresses.The inappropriate use of a cutting torch created an untempered martensiticheat-affected zone in the high-carbon steel rail. This zone was especiallysensitive to hydrogen cracking and subsequent brittle crack propagation. Thecrack inducing and propagating loading was primarily due to bending of the604 E tII" -' IN 96-26April 30, 1996 rail head to the outside during episodes of rail misalignment. The licenseehad observed rail misalignment to be a continuing problem that had caused orcontributed to 19 bridge truck wheel bearing failures over 23 years ofoperation.The root cause of the failure was the inappropriate use of a cutting torch toenlarge drilled holes to slots in the web of the rail. This practice createdan untempered, martensitic, heat-affected zone in the rail material that wassensitive to hydrogen cracking and subsequent brittle crack propagation.Actuation of Overhead Crane Safety SystemAt the Prairie Island Nuclear Generating Plant on May 13, 1995, while liftinga loaded spent fuel storage cask from the spent fuel pool for transfer to thetransport bay, the single-failure-proof overhead crane handling systemautomatically stopped on overload, approximately 13 cm (5 inches] from thehigh hook point (peak lift point). The bottom of the cask was above the waterbut approximately 8 cm [3 inches] below the operating deck of the spent fuelpool. Upon investigation of the event, the licensee, Northern States PowerCompany (NSP) determined that the cause of the event was premature actuationof the crane overload-sensing system. The setpoint on the overload-sensingsystem was set too low. Upon actuation of the overload-sensing system,control power is automatically removed from the hoist motor and theconventional holding brakes are activated. Subsequent to the actuation onMay 13, the cask remained in the hoisted position until a safety evaluationwas made that supported bypassing the sensing system and resuming the casklift. The lift was resumed about 16 hours1.851852e-4 days <br />0.00444 hours <br />2.645503e-5 weeks <br />6.088e-6 months <br /> after it was stopped, and the caskwas placed in the decontamination area of the transport bay. NSP initiated aroot-cause analysis to identify the cause of the actuation. The conclusion ofthis analysis was that the overload-sensing system was inaccuratelycalibrated.This event raises a concern for similarly designed overload-sensing systemsassociated with single-failure-proof cranes. As noted in the analysisreports, this event was a "nuisance trip" that resulted from inaccurateinitial calibration during load cell setting adjustment. Improved load cellaccuracy can help to reduce any unbalanced loading condition in the system.Additional details of these events can be found in Inspection ReportNo. 50-344/95-06 issued on September 18, 1995, and Inspection ReportNo. 50-282/95-06 issued on June 27, 199 '2 ' IN 96-26April 30, 1996 This information notice requires no specific action or written response. Ifyou have any questions about the information in this notice, please contactone of the technical contacts listed below. ABrian K. Grimes, Acting DirectorDivision of Reactor Program ManagementOffice of Nuclear Reactor RegulationTechnical contacts:Robert J. Pate, Region IV(510) 975-0246Internet:rjpl@nrc.govDavid B. Pereira, Region IV(510) 975-0307Internet:dbp@nrc.govBrian E. Thomas, NRR(301) 415-1210Internet:betfnrc.govEric J. Benner, NRR(301) 415-1171Internet:ejbl@nrc.govRussell L. Bywater, Region III(612) 388-8209Internet:rlb3@nrc.govAttachme: List of Recently I ued NRC Information Noticeskay r P s
' JAttachmentIN 96-26April 30, 1996 LIST OF RECENTLY ISSUEDNRC INFORMATION NOTICESInformation Date ofNotice No. Subject Issuance Issued to96-2596-2496-2396-2296-21Transversing In-Core ProbeOverwithdrawn at LaSalleCounty Station, Unit 1Preconditioning of Molded-Case Circuit BreakersBefore Surveillance TestingFires in Emergency DieselGenerator Exciters DuringOperation Following Unde-tected Fuse BlowingImproper Equipment Set-tings Due to the Use ofNontemperature-CompensatedTest EquipmentSafety Concerns Relatedto the Design of the DoorInterlock Circuit onNucletron High-Dose Rateand Pulsed Dose RateRemote AfterloadingBrachytherapy DevicesDemonstration of Associ-ated Equipment Compliancewith 10 CFR 34.20Failure of Tone AlertRadios to Activate WhenReceiving a ShortenedActivation SignalCompliance with 10 CFRPart 20 for AirborneThorium04/30/9604/25/9604/22/9604/11/9604/10/9604/04/9604/02/9603/25/96All holders of OLs or CPsfor nuclear power reactorsAll holders of OLs or CPsfor nuclear power reactorsAll holders of OLs or CPsfor nuclear power reactorsAll holders of OLs or CPsfor nuclear power reactorsAll U.S. NRC Medical to theLicensees authorized to usebrachytherapy sources inhigh- and pulsed-dose-rateremote afterloadersAll industrial radiographylicensees and radiographyequipment manufacturersAll holders of OLs or CPsfor nuclear power reactorsAll material licenseesauthorized to possess anduse thorium in unsealedform96-2096-1996-18OL = Operating LicenseCP = Construction Permit IN 96-26April 30, 1996 This information notice requires no specific action or written response. Ifyou have any questions about the information in this notice, please contactone of the technical contacts listed below.dbvtRA7 by Man K. GrmesBrian K. Grimes, Acting DirectorDivision of Reactor Program ManagementOffice of Nuclear Reactor RegulationTechnical contacts:Robert J. Pate, Region IV(510) 975-0246Internet:rjpl@nrc.govDavid B. Pereira, Region IV(510) 975-0307Internet:dbp@nrc.govBrian E. Thomas, NRR(301) 415-1210Internet:bet@nrc.govEric J. Benner, NRR(301) 415-1171Internet:ejbl@nrc.govRussell L. Bywater, Region III(612) 388-8209Internet:rlb3@nrc.gov
Attachment:
List of Recently Issued NRC Information NoticesTech Editor Reviewed and Concurred 1/26/96*ETB FOR**SEE PREVIOUS CONCURRENCENAME: 96-26.INTo receive a copy of this document. Indicate in the box: wC" = Copy without enclosures 'E' = Copy with enclosures "N" = No copyOFFICE TECH CONTS I PECB:DRPMl AD:DRPM 1b1 1 1NAME RJPate* AChaffee* BKGri 7BEThomas*DBPereira*EJBenner*RLBywater* _ __ leDATE 01/30/96 04/16/96 04 /961 1 96OFFICIAL RECORD COPY
'~JIN 96-xxApril xx, 1996 This information notice requires no specific action or written response. Ifyou have any questions about the information in this notice, please contactone of the technical contacts listed below.Dennis M. Crutchfield, DirectorDivision of Reactor Program ManagementOffice of Nuclear Reactor RegulationTechnical contacts:Robert J. Pate, Region IV(510) 975-0246Internet:rJplnrc.govDavid B. Pereira, Region IV(510) 975-0307Internet:dbp~nrc.govBrian E. Thomas, NRR(301) 415-1210Internet:bet~nrc.govEric J. Benner, NRR(301) 415-1171Internet:ejbl@nrc.govRussell L. Bywater, Region III(612) 388-8209Internet:rlb3@nrc.gov
Attachment:
List of Recently Issued NRC Information NoticesTech Editor Reviewed and Concurred 1/26/96*ETB FOR**SEE PREVIOUS CONCURRENCE NAME: G:\JRT\CRANE3.INTo receiVe a copy of thi docunent, hdicate hI the box: 'C- Copy without enclosures 'E' M Copy with enclosures W -No copyOFFICE Contacts** C/SPLB:DSSA** PECB:DRPM** I PECB:DRPI4 D DRPMNAME RJPate* CMcCracken EGoodwin AChaffee DCrutchfieldBEThomas*DBPereira* efAEJBenner*DATE___ RLBywater* 0106___rY__9__ 4 /DATE 01/30/96 0/1I/30/96 04/09/96 04/1, /96 -;P 104/ /96UrIULAL KtlMUKU CurlIvt,;,a e 96-xxApril xx, 1996 Additional details of these events can be found in Inspection ReportNo. 50-344/95-06 issued on September 18, 1995 and Inspection ReportNo. 50-282/95-06 issued on June 27, 1995. This information notice requ r --tiospecific action or written response. If you have any questions about theinformation in this notice, please contact one of the technical conta slisted below.Dennis M. Crutchfiel i DirectorDivision of Reactor rogram ManagementOffice of Nuclear eactor RegulationTechnical contacts:Robert J. Pate, Region IV Brian E. omas, NRR(510) 975-0246 (301) 4 -1210Internet: rjpl@nrc.gov Intern : betenrc.govDavid B. Pereira, Region IV EriJ. Benner, NRR(510) 975-0307 (3 1) 415-1171Internet: dbp@nrc.gov Jnternet: ejbl@nrc.govRussell L. Bywater, Region III(612) 388-8209Internet: rlb3@nrc.gov
Attachment:
List of Recentl Issued NRC Information NoticesTech Editor Reviewed and ncurred 1/26/96*ETB FOR**SEE PREVIOUS CONCUR5NCE NAME: G:\JRT\CRANE3.IN_- t- ..... -wI-t ---nZf!- '_n &,__.u *nbsrs ._ Co -- -'F 'nvy wlth iark-laneures 1NJ -No coovIT lcolwV a copy al WIu swoumilE Wugulfl-ll.se U-UI-.U A--. - -* --- -rOFFICE Contacts** l C ISPLB:DSSA** l PECB:DRPM** PECB:DRPl Dl0RPMNAME RJPate* )McCracken EGoodwin AChaffee DCrutchfieldBEThomas*DBPereira*EJBenner*RLBywater* /DATE 01/30/96 / 0/1/30/96 04/09/96 04/ /96 04/ /96UI-ILIAL KtLUKLJ LUVIje MW
\2 KlI .IN 96-xxApril xx, 1996 Additional details of these events can be found in Inspection ReportNo. 50-344/95-06 issued on September 18, 1995 and Inspection ReportNo. 50-282/95-06 issued on June 27, 1995. This information notice requires nospecific action or written response. If you have any questions about theinformation in this notice, please contact one of the technical contactslisted below.Dennis M. Crutchfield, *rectorDivision of Reactor Pr gram ManagementOffice of Nuclear Re ctor RegulationTechnical contacts:Robert J. Pate, Region IV Brian E. Thomas, RR(510) 975-0246 (301) 415-1210Internet: rjpl@nrc.gov Internet: be nrc.govDavid B. Pereira, Region IV Eric J. B ner, NRR(510) 975-0307 (301) 4 -1171Internet: dbp@nrc.gov Inter t: ejblnrc.govRussell L. Bywater, Region III(612) 388-8209Internet: rlb3@nrc.gov
Attachment:
List of Recently ssued NRC Information NoticesTech Editor Reviewed and C curred 1/26/96*ETB FOR**SEE PREVIOUS CONCU ENCE E_(___9OFFICE Contact
- C/SPLB:DSSA** C/PECB:DRPM D/DRPMlME RJPa
- CMcCracken AChaffee DCrutchfieldBET omas*D ereira*JBenner*_RLBywater*DATE 01/30/96 01/30/96 / /96 / /96Official Record CopyDOCUMENT NAME: S:\JRT\CRANE3.IN K>IN 96-xxMarch xx, 1996 More detailed descriptions of these events are included in Attachment 1 tothis Information Notice. This information notice requires no specific actionor written response. If you have any questions about the information in thisnotice, please contact one of the technical contacts listed below.1"Dennis M. Crutchfield, Di etorDivision of Reactor Pro am ManagementOffice of Nuclear Rea or RegulationTechnical contacts:Robert J. Pate, Region IV Brian E. Thomas,(510) 975-0246 (301) 415-1210Internet: rjplenrc.gov Internet: bet@ c.govDavid B. Pereira, Region IV Eric J. Ben r, NRR(510) 975-0307 (301) 415i 171Internet: dbp~nrc.gov Internet ejbl@nrc.govRussell L. Bywater, Region III(612) 388-8209Internet: rlb3@nrc.gov
Attachment:
List of Recently Iss ed NRC Information NoticesTech Editor Reviewed and Concu ed 1/26/96*ETB FOR**SEE PREVIOUS CONCURRENCE /_____OFFICE Contacts** X/SPLB:DSSA** C/PECB:DRPM D/DRPMl E RJPate* CMcCracken AChaffee DCrutchfieldBEThomas*DBPereira*EJBenner*_LBywatO*DATE 01/36./96 01/30/96 / /96 / /96Official Record CopyDOCUMENT NAME:S:\JRT\CRANE2.IN
\K>IN 96-xxFebruary xx, 6 Technical contacts:Robert J. Pate, Region IV Brian E. Thomas, NRR(510) 975-0246 (301) 415-1210Internet: rjpl@nrc.gov Internet: bet@nrc.govDavid B. Pereira, Region IV William F. Burton, NRR(510) 975-0307 (301) 415-2583Internet: dbp~nrc.gov Internet: wfblnrc.gRussell L. Bywater, Region III(612) 388-8209Internet: rlb3@nrc.gov
Attachment:
List of Recently Issued NRC Info iaton NoticesOV, eVy-Vnet LoX +§ wt A1 ne d I aSntoTech Editor Reviewed d Concurred 1/26/96OFFICE Contacts C/SPLB:DSSA C/PECB:DRPM D/DRPM"NE RJPate / CMcCracken + AChaffee DCrutchfieldBEThomsDBPer irarWFBu ton*#_ _ RLB ater__DATE /o / /CI /96 / /96 / /96Official Record CopyDOCUME NAME: G:\JRT\CRANE2.IN